The PNG is encoded with an alpha channel, and the lower 269 scanlines contain an additional stream of bytes.

Extract the data, making sure your method begins at the last pixel, traveling left and up, then re-save the data (344320 bytes) as an MP4 file.

Inside this file is more meta data that reads:

Movie Name: RECOVERED FRAGMENT

Album: REQUIEM ARCHIVE I

Recorded date: 2557

Comment: /START FILE//CLASSIFIED//ONI HAS RECEIVED UNCONFIRMED REPORTS FROM FIELD OPERATIVES, REGARDING PREVIOUSLY UNKNOWN EMBLEM PATTERNS WHICH MAY BE APPLIED TO SPARTAN-IV ARMOR. THE EXACT MECHANISM IS UNCLEAR, HOWEVER IT MAY BE RELATED TO THE...

Extract the greyscale 0-255 pixel values for each pixel and save as raw files. There are many ways this can be done. The resulting binary files are additional PNG images, as below

One exception: The blue plane PNG has extra text content embedded in its binary (making it an invalid PNG as is). With the data extracted, boost the brightness to see the hidden symbol. Extracted from the file is the following text:

/START FILE//CLASSIFIED//RAIDER/EARLY REPORTS FROM IMBRIUM MACHINE COMPLEX FACILITY ARE POSITIVE - TESTING IS STILL UNDERWAY BUT SO FAR THE TEST SUBJECTS EXHIBIT THE DESIRED EFFECTS FROM THE UPDATED FERAL DESIGN./END FILE/

GLYPHS CAN BE COMBINED TO FORM CODES, WHICH CAN BE USED TO UNLOCK CLASSIFIED DATA, VIA AUTHORIZED WAYPOINT TERMINALS.

CODES ARE TIED TO SPECIFIC PREREQUISITES WHICH MUST BE MET BY THE OPERATIVE PRIOR TO UNLOCKING THE DATA. PREREQUISITES APPEAR TO BE ASSOCIATED TO THE COMPLETION OF SPECIFIC UNSC MISSION OBJECTIVES. MORE RESEARCH IS NEEDED IN THIS AREA.

SEQUENCING OF THE GLYPHS INTO CODES IS NOW DETERMINED BY INTERLOCKED CONTAINERS (IT WAS PREVIOUSLY DETERMINED VIA GLYPH SEMANTICS, FOR THE ALPHA HALO ARCHIVE CODES).

/START FILE///CLASSIFIED/////ALERT! ALL PERSONNEL MUST IMMEDIATELY ENGAGE IN THE ONGOING EFFORT TO UNSCRAMBLE THE "TIME CAPSULE" DATANODE/////DATANODE CURRENT LOCATION:download.halowaypoint.com/content/waypoint/assets/images/classified/0000timecapsule/1jk4giqwr67g3af97qwyg739-timecapsule.html/////END FILE/

b) Following the meta Description, link to a url which displays:0000-????-???W-????-?-???Z-???-????-????-???-?0?8-??7-???8-W???-?47-??W-?00?-?0?-????-W???-????-?Y??-????-??Y-Y???-????-???-?0?-???Y-???-????-???-??W-?6??-????-???-W???-???-????-W??-??Z4-?0?-???W-????-???-????-????-??7-???0-??Z?-????-??0?

p1) At the end of the trailer is a single frame with the ONI symbol, and when viewed and enhanced contains a faint outline of a puzzle piece.

p2) Near the end of the trailer at the title sequence, there's a quiet audio squeal[2]. This is another spectrogram, which when analyzed produces the following symbol, combined below with the puzzle frame:

When viewed with a hex editor, the file appears to be a WAV formatted file. Interleaved with the WAV data, however, are null (00) value bytes. Removing the WAV syntax segments and these null bytes produces a hidden GIF file, which contains the glyph for "V":

Orphaned Glyphs

Reference puzzles

Recipe

From forum post containing:

/START FILE//CLASSIFIED/ONI FIELD MANUAL EXCERPT/ON ASSIGNMENT, IT IS OFTEN NECESSARY TO IMPROVISE IN ORDER TO STAY HEALTHY AND WELL FED. ONI DOES NOT EXPECT ALL PERSONNEL TO BE CULINARY EXPERTS, BUT YOU MUST UNDERSTAND BASIC PRINCIPLES AND RECIPES. RECIPES ARE CRUCIAL, AS THEY ALLOW YOU TO CONVERT TWO SEEMINGLY DISPARATE INGREDIENTS, INTO A WONDERFUL DISCOVERY OF FLAVOR.//END FILE/